It's here: the GIMP 2.8. Its biggest feature is something that many, many people have been requesting for as long as I can remember: single-window mode. No longer do you have to fiddle with a gazillion palette and dialog windows (unless you choose to do so, of course). Great work by the team.

Well, is that actually true? Does Pixelmator have more downloads than GIMP? More users? More books published about it? I haven't seen any firm numbers, but I wouldn't a priori assume that Pixelmator has a larger userbase than GIMP.